include/linux/huge_mm.h

   1 #ifndef _LINUX_HUGE_MM_H
   2 #define _LINUX_HUGE_MM_H
   3
   4 extern int do_huge_pmd_anonymous_page(struct mm_struct *mm,
   5                                       struct vm_area_struct *vma,
   6                                       unsigned long address, pmd_t *pmd,
   7                                       unsigned int flags);
   8 extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
   9                          pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
  10                          struct vm_area_struct *vma);
  11 extern int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
  12                                unsigned long address, pmd_t *pmd,
  13                                pmd_t orig_pmd);
  14 extern pgtable_t get_pmd_huge_pte(struct mm_struct *mm);
  15 extern struct page *follow_trans_huge_pmd(struct mm_struct *mm,
  16                                           unsigned long addr,
  17                                           pmd_t *pmd,
  18                                           unsigned int flags);
  19 extern int zap_huge_pmd(struct mmu_gather *tlb,
  20                         struct vm_area_struct *vma,
  21                         pmd_t *pmd);
  22 extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  23                         unsigned long addr, unsigned long end,
  24                         unsigned char *vec);
  25 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  26                         unsigned long addr, pgprot_t newprot);
  27
  28 enum transparent_hugepage_flag {
  29         TRANSPARENT_HUGEPAGE_FLAG,
  30         TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
  31         TRANSPARENT_HUGEPAGE_DEFRAG_FLAG,
  32         TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
  33         TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
  34 #ifdef CONFIG_DEBUG_VM
  35         TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
  36 #endif
  37 };
  38
  39 enum page_check_address_pmd_flag {
  40         PAGE_CHECK_ADDRESS_PMD_FLAG,
  41         PAGE_CHECK_ADDRESS_PMD_NOTSPLITTING_FLAG,
  42         PAGE_CHECK_ADDRESS_PMD_SPLITTING_FLAG,
  43 };
  44 extern pmd_t *page_check_address_pmd(struct page *page,
  45                                      struct mm_struct *mm,
  46                                      unsigned long address,
  47                                      enum page_check_address_pmd_flag flag);
  48
  49 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  50 #define HPAGE_PMD_SHIFT HPAGE_SHIFT
  51 #define HPAGE_PMD_MASK HPAGE_MASK
  52 #define HPAGE_PMD_SIZE HPAGE_SIZE
  53
  54 #define transparent_hugepage_enabled(__vma)                             \
  55         (transparent_hugepage_flags & (1<<TRANSPARENT_HUGEPAGE_FLAG) || \
  56          (transparent_hugepage_flags &                                  \
  57           (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&                    \
  58           (__vma)->vm_flags & VM_HUGEPAGE))
  59 #define transparent_hugepage_defrag(__vma)                              \
  60         ((transparent_hugepage_flags &                                  \
  61           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)) ||                     \
  62          (transparent_hugepage_flags &                                  \
  63           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG) &&             \
  64           (__vma)->vm_flags & VM_HUGEPAGE))
  65 #ifdef CONFIG_DEBUG_VM
  66 #define transparent_hugepage_debug_cow()                                \
  67         (transparent_hugepage_flags &                                   \
  68          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
  69 #else /* CONFIG_DEBUG_VM */
  70 #define transparent_hugepage_debug_cow() 0
  71 #endif /* CONFIG_DEBUG_VM */
  72
  73 extern unsigned long transparent_hugepage_flags;
  74 extern int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
  75                           pmd_t *dst_pmd, pmd_t *src_pmd,
  76                           struct vm_area_struct *vma,
  77                           unsigned long addr, unsigned long end);
  78 extern int handle_pte_fault(struct mm_struct *mm,
  79                             struct vm_area_struct *vma, unsigned long address,
  80                             pte_t *pte, pmd_t *pmd, unsigned int flags);
  81 extern int split_huge_page(struct page *page);
  82 extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd);
  83 #define split_huge_page_pmd(__mm, __pmd)                                \
  84         do {                                                            \
  85                 pmd_t *____pmd = (__pmd);                               \
  86                 if (unlikely(pmd_trans_huge(*____pmd)))                 \
  87                         __split_huge_page_pmd(__mm, ____pmd);           \
  88         }  while (0)
  89 #define wait_split_huge_page(__anon_vma, __pmd)                         \
  90         do {                                                            \
  91                 pmd_t *____pmd = (__pmd);                               \
  92                 spin_unlock_wait(&(__anon_vma)->root->lock);            \
  93                 /*                                                      \
  94                  * spin_unlock_wait() is just a loop in C and so the    \
  95                  * CPU can reorder anything around it.                  \
  96                  */                                                     \
  97                 smp_mb();                                               \
  98                 BUG_ON(pmd_trans_splitting(*____pmd) ||                 \
  99                        pmd_trans_huge(*____pmd));                       \
 100         } while (0)
 101 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
 102 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
 103 #if HPAGE_PMD_ORDER > MAX_ORDER
 104 #error "hugepages can't be allocated by the buddy allocator"
 105 #endif
 106 extern int hugepage_madvise(unsigned long *vm_flags);
 107 extern void __vma_adjust_trans_huge(struct vm_area_struct *vma,
 108                                     unsigned long start,
 109                                     unsigned long end,
 110                                     long adjust_next);
 111 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 112                                          unsigned long start,
 113                                          unsigned long end,
 114                                          long adjust_next)
 115 {
 116         if (!vma->anon_vma || vma->vm_ops || vma->vm_file)
 117                 return;
 118         __vma_adjust_trans_huge(vma, start, end, adjust_next);
 119 }
 120 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 121 #define HPAGE_PMD_SHIFT ({ BUG(); 0; })
 122 #define HPAGE_PMD_MASK ({ BUG(); 0; })
 123 #define HPAGE_PMD_SIZE ({ BUG(); 0; })
 124
 125 #define transparent_hugepage_enabled(__vma) 0
 126
 127 #define transparent_hugepage_flags 0UL
 128 static inline int split_huge_page(struct page *page)
 129 {
 130         return 0;
 131 }
 132 #define split_huge_page_pmd(__mm, __pmd)        \
 133         do { } while (0)
 134 #define wait_split_huge_page(__anon_vma, __pmd) \
 135         do { } while (0)
 136 static inline int hugepage_madvise(unsigned long *vm_flags)
 137 {
 138         BUG();
 139         return 0;
 140 }
 141 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 142                                          unsigned long start,
 143                                          unsigned long end,
 144                                          long adjust_next)
 145 {
 146 }
 147 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 148
 149 #endif /* _LINUX_HUGE_MM_H */